Delhi’s air quality took a sharp decline on Wednesday evening, with the Air Quality Index (AQI) surpassing the 450-mark, entering the ‘severe plus’ category. The overall AQI reading at 11 pm was recorded at 450, marking a significant spike from the 442 reading earlier in the day at 7 am.
The deteriorating air quality has been attributed to a combination of low temperatures and weak winds, which are hindering the dispersal of pollutants. The city has witnessed a decline in air quality over the past few days, exacerbating the health risks for residents.
Nehru Nagar (485), Wazirpur (482), Rohini (478), Anand Vihar (478), and Punjabi Bagh (475) were among the most polluted areas, according to the CPCB’s Sameer app, which tracks hourly air quality for over 100 cities across India.
A dense fog blanketed the city throughout the day, adding to the discomfort with a pungent air quality that persisted in several localities.The maximum temperature recorded was 23°C, slightly above the season’s average, while the minimum temperature dropped to 7.6°C, slightly below the usual seasonal norms.

On Tuesday, Delhi’s 24-hour average AQI was 433 at 4 pm, compared to 379 on Monday, signaling a sharp worsening of the air quality.
In response to the worsening pollution levels, Delhi continues to remain under Stage-IV of the Graded Response Action Plan (GRAP), which enforces stringent anti-pollution measures, including a ban on construction activities and restrictions on the entry of non-essential polluting trucks into the city.
An AQI reading of 400 or above calls for urgent measures, according to CPCB guidelines. GRAP categorizes air quality into four stages: Stage-I (Poor, AQI 201-300), Stage-II (Very Poor, AQI 301-400), Stage-III (Severe, AQI 401-450), and Stage-IV (Severe Plus, AQI above 450).
In light of the worsening pollution, Delhi-NCR schools on Tuesday shifted to a hybrid mode of learning. Under Stage 4 of GRAP, classes for students in grades 6-9 and 11 in Delhi, Gurugram, Faridabad, Ghaziabad, and Gautam Buddh Nagar are being conducted in a hybrid mode, combining physical and online lessons. However, students in grades 10 and 12 are still required to attend in-person classes.
This move follows the earlier re-imposition of hybrid learning after schools had briefly resumed in-person classes on December 5, following a temporary switch to hybrid mode on November 25.